An improvement in the nozzles/screens used in the fluid processing units

ABSTRACT

The invention relates to an improvement in nozzles/screen for fluid flow distribution/collection used In fluid flow distribution/collection used In fluid processing units. Improvement in conventions nozzle/screen comprises a flow restricting cylindrical body to have ring washer shape aperture control at inlet/outlet. The improved nozzle/screen comprises outer casing made of stacked flat rings with micro opening between said stacked ring providing uniform throughout its periphery. A central conduit having holes for flow of fluid entering through the said outer casing. The said conduit having means to regulate fluid flow.

FIELD OF THE INVENTION

Present invention relates to improvement in the “different designs ofnozzles/screens used in fluid processing units for fluiddistribution/collection. More particularly, present invention relates toimprovement of current wedge wire screens & developing its equivalent inplastics, for flow distribution & collection systems in differentprocess applications, such as: ion-exchange units, adsorption columns,media filters & candle filters to improve its overall working efficiency& minimizing manufacturing cost.

BACKGROUND OF THE INVENTION (PRIOR ART)

There are variety of the nozzles developed, depending upon theapplications, but we will consider the various nozzles/strainers usedfor fluid processing units only. In the processing units such as mediafilters, adsorption columns & ion exchange units, various types ofnozzles had been developed (as referred in the citations) for theinternals. The general construction details are that these nozzles arehaving cylindrical, semi-circular, conical-tapered closed shapes & usingtheir first, outermost body as a boundary having apertures for fluidtransport. These apertures are either vertical slots, cross-mesh orhorizontal slots. The second boundary inside using apertures of circularshape or slots or mesh. The fluid transport takes place through singleor multiple boundaries through a conduit or pipe in which area of crosssections are successively reduced to increase velocity of the fluid.

The prior art nozzles using mesh type aperture openings, as their firstboundary are the worst type of nozzles due to clogging problems & hadbeen already addressed by number of developers.

The prior art nozzles using horizontal slots formed by wedge-wires hadbeen proved the most effective, as they have highest fluid transportarea & non-clogging properties. These wedge-wire-screen nozzles are madeof metals only; such as SS304, SS316, SS316L & Nikel alloys (Such asHastelloy). The prices of such nozzles screens are very high compared tomany nozzles made from thermoplastics, while considering corrosionresistance properties. Due to high fluid transport ability, these nozzlescreens deliver/collect different quantities of fluid in a unit time dueto variable fluid transporting distances from the centraldistribution/collection point. This drawback remains in almost all othertypes of screen nozzles also.

Almost all circular/cylindrical wedge-wire-screens are using closelypitched wedge wires as their primary filtering surface & secondary fluidtransporting & controlling apertures on inside conduit or conicalshaped, closed capsulated metallic container. The container withapertures is connected to inlet/outlet nozzle pipe. The ratio of netaperture area of primary wedge-wire screen & area of the apertures onsecondary container inside decides the fluid transport parameters. Inthis case, the aperture changes, due to wear, results uneven fluidtransport.

Fluid collection/distribution through wider angle (nearly 360°) is theclassic feature of this cylindrical profile arrangement of the wedgewire screen nozzles, but fluid collection/distribution through multipleapertures inside induces uneven fluid profile outside.

The prior art wedge wire screens are required to be replaced completelywhen the aperture sizes changes beyond permissible limits due to wear.

The individual nozzle position w.r.t. delivery/collection point is notconsidered in the “variable flow screen nozzles” presented in thecitation (U.S. Pat. No. 5,658,459 & US 20120037730). When using suchnozzles on the header-lateral type of bottom collector, they bound todeliver different quantities of fluid in the counter-flow & co-flow.Similarly, when using such nozzles on the collection plate at the bottomof the processing vessel, for example, an ion-exchange unit, thecounter-current regeneration chemical injection has dilution effect dueto dead volume of water present in the bottom of the vessel, belowcollection plate. In case of the ion-exchangers using higher diameter ofpressure vessels, the bottom dead volume of water has significantdilution effect on the injection chemical intended for counter-currentflow & therefore certain higher amount of chemical dosing is inevitableeven after having excellent “distribution screen nozzle”.

OBJECTIVES OF THE INVENTION

The primary objective of the invention is to develop substitute nozzlessystem for wedge-wire screens (MOC—Metals) having high flow rate perunit surface area & non-cogging features, using suitable thermoplasticshaving very high corrosion resistant properties & minimum wear rateagainst fluid flows for higher working life span.

Another objective is to develop stack ring of the nozzles enclosure withoptimum thickness & width with suitable supporting features to retainstability at different pressure conditions.

Yet another objective of the stack ring development is to achievehighest degree of fluid transporting angle through its peripheral way(nearly 360 deg.). Yet another objective of the invention is to developvariable flow nozzle with easy construction features. For example, easyassembly & maintenance of the diffuser/strainer stack of the nozzles.

Another objective of the nozzle development is to achieve equal flowdistribution/collection through their connecting laterals & headersalso, of the system.

Another objective of the innovation is to achieve flow control of thewedge-wire screen as per locations to achieve uniform flow velocities,which is required in number of process column operations.

Yet another objective of the nozzle development is to achieve betterprocess efficiencies of the working columns, where the said nozzles arecomponents of the distribution & collection network.

STATEMENT OF INVENTION

Accordingly invention provides an improvement in the conventionalnozzles/screen for fluid flow distribution/collection used in fluid flowprocessing units comprises wedge wire screen (02) of wedge wire profiles(208) wound cylindrically, with pitch 206 a to form a screen (210 a) &welded with vertical rods (207) to form an open cylinder from its eitherside; characterised in that a pair of threaded couplings (228, 229)having external diameter nearly equal to the cylinder of the screen 210a is welded from either of its openings; one of the said coupling (229)height is kept minimum, just to introduce a flow restrictor 30 and thesaid other end coupling (228) is standard to receive piping connection(34); a flow restrictor 30 is made of plastic (e.g. PP, PVDF; UHMWPE)having basic cylindrical shape, having threaded end (229 a) matchingwith the said short coupling end (429) for introducing inside the screencylinder (210 a); the said fluid restrictor (30), given taper (231)nearly up to half-way mark of the screen (210 a) height, and thereafterturned into cylindrical shape (232) with conical tip (233) such that thesaid cylindrical shape (232) of the flow restrictor (30) passing throughend coupling (228) makes washer shape orifice (235) with internal faceof the pipe connection (34).

According to one embodiment the invention provides an improvednozzles/screen for fluid flow distribution/collection used in fluidprocessing units comprises a cylindrical outer casing of screen made ofnumber of stacked rings, having taper towards centreonane side and flatother side or tapered both sides or flat both sides, having definedwidth and thickness with radially extending number of lugs formedtherein with thickness slightly more than that of said ring to givedesired gap between the said stacked rings; a central conduit withthreaded ends located at the centre of said outer casing with the helpof the said lugs having equal lengths just touching periphery of thesaid conduit & at least one of the lug having extended length; the saidone of the lug is having extended length to engage a slot in the saidconduit; the said conduit provided with number of holes at distant inline in each of channel formed by said adjacent lugs; the said outercasing held by check nut or threaded ring in the said conduit; the saidconduit is provided with a flow restrictor (30C), having tapered,conical shape such that the highest cylindrical end can enclose theconduit from inside from one end; the said flow restrictor (30C)inserted from the opposite end to that of fluid distribution/collectionend so that enclosing it from opposite end & the tapered end pointingtowards the fluid distribution/collection end.

According to the second embodiment the invention provides an improveddistribution/collection through plurality of improved nozzles connectedto number of laterals (pipes) or the laterals themselves formed ofperforated pipes (532); the laterals connected to another header (pipe)intended for fluid collection/distribution; the header-lateral assemblyremain on one single plane; the laterals & the header pipes are appliedwith flow restrictors (30/30A/30B); the said flow restrictor havingbasic cylindrical (bar) shape closing the respective dead end of thepipes from inside (533) & cantilevered; the said flow restrictors(30/30A/30B) of the lateral or header has given taper towardsdistribution/collection end; the said taper of the flow restrictor (30A)may have two sided chamfer (534) or in another case the flow restrictor(30B) may have one sided chamfer, depending on sub branching (537/537B)of the header.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. No: 01 (Prior Art) shows the vertical & horizontal (SECTION-I)cross section of a ‘wedge wire screen’ nozzle & its constructiondetails.

FIG. No: 02A shows a vertical cross section of “improved wedge wirescreen” & its details.

FIG. No: 02E shows a vertical section of the “flew restrictor” (30) &its details.

FIG. No: 02C shows a vertical section of the “improved wedge wire screenassembly” NOZZLE-A & its sectional view (SECTION-II).

FIG. No: 02D shows 3D view of the “Row restrictor” (30) & its details.

FIG. No: 02E shows 3D view of the “improved wedge wire screen assembly”& its details.

FIG. No: 03A shows TOP & BOTTOM view of the “Stack Ring Type-I” & itsfeatures.

FIGS. No: 03B & 03C shows the SECTION-III of the stack ring type-I &its' details after stacking.

FIG. No: 04A shows TOP & BOTTOM view of the “Stack Ring Type-II” & itsfeatures.

FIGS. No: 04B & 04C shows the SECTION-IV of the stack ring type-II &its' details after stacking.

FIG. No: 05A shows NOZZLE-B assembly details using stack rings of Type-Ior Type-II.

FIG. No: 05B shows vertical cross section of the NOZZLE-B without stackrings & their details.

FIG. No: 05C shows vertical cross section of the NOZZLE-B with “flowrestrictor” loading but without stack rings loading.

FIG. No: 06A shows details of the SECTION-V, in which stack ringinterlocking with nozzle conduit is elaborated.

FIG. No: 06B snows ‘Blank Ring’ used for supporting & partitioning themain stack-rings assembly.

FIG. No: 07A shows cross-section of a pressure vessel having‘Header-Lateral’type distribution/collection system with main headerapplied with “flow restrictor” applications branches with improvednozzles.

FIG. No: 07B shows ‘Front View & Top View’ of a cylindrical (Bar shaped)shaped “flow restrictor” with two-side chamfers.

FIG. No: 07C shows horizontal cross section of a header (Tap View),having laterals connections on its either sides & containing flowrestrictor with either two-sided chamfer (taper) or conical shape.

FIG. No: 07D shows ‘Front View & Top View’ of a cylindrical (Bar shaped)shaped “flow restrictor” with one-side chamfer.

FIG. No: 07E shows horizontal cross section of a header (Front View),having laterals connections on its bottom & containing flow restrictorwith one-sided chamfer (taper).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Prior to giving details of the preferred embodiments, we would like tobrief out the development for easy understanding for the presentdisclosure given below.

“Flow distribution nozzle systems” consists' of a set of nozzles usedfor fluid processing units for fluid distribution/collectionapplications under varied physical parameters. In the presentdisclosure, an attempt made to explain development work related to:

-   -   1) Improved wedge wire screens for accurate flow control.    -   2) Plastic nozzles substitute to wedge wire screen nozzles.    -   3) Improved “Header-Lateral” distribution & collection by        applying flow restrictors.

The following description of the parts S body components, represented bynumeral annotations, elaborates prior art & the development work:

FIG. No 01 (Prior Art) represents a typical wedge wire screen 01, forwhich a plastic nozzle/screen substitute development, is intended. Wedgewire 06 of nearly triangular shape is wound in cylindrical shape bygiving pitch (gap) 06 a for fluid transport 10. Pitch between twosuccessive wires is given to separate smallest media particles from theinterior cavity of the screen & it also defines the single minimumaperture area developed at its circumference for fluid transport.

The total wedge wire screen cylinder 10 a defines the total availablearea of fluid transport at its peripheral surface. From inside of thewedge wires screen cylinder, vertical rods 07 are welded at equidistancefor physical stability. The vertical rods 07 are also welded to the topcircular cap 18 a, which closes the screen from one end. The bottomcircular cap 18 b having central inlet/outlet port 11 closes the bottomof the screen cylinder. A cylindrical cup shaped fluid restrictor 08 a.having lesser diameter than screen, having apertures 09 uniformly spreadover its' cylindrical surface, is welded inside the bottom closing cap18 b at the centre, at its' open end. The total aperture area of thefluid restrictor 08 a formed by apertures 09 is less than the totalaperture area of the wedge wire screen at its periphery. An orifice ring09 a having circular opening of diameter d0, is fixed at the entry ofthe nozzle port 11. The area of the orifice ring 09 a (d0) is less thanthe total area of the openings 09 on the fluid restrictor 08 a.

Thus, the first boundary of fluid transport is defined by wedge wirescreen peripheral openings, the second by the total openings on fluidrestrictor 08 a & the third by orifice opening 09 a (d0). The ratio ofthe net areas of the successive boundaries influences the fluidtransport or Nozzle/Diffuser action. Therefore, the change of aperturesdue to wear of the metals results uneven flow parameters.

The improvement in the conventional wedge-wire-screens is achieved byintroducing a flow restrictor (30) in the nozzles, its connectinglaterals (532) & main header (531). The application of flow restrictor(30, 30A, 30B) achieves uniform distribution/collection in theprocessing vessel.

FIGS. No: 02A, 02B & 02C elaborates the improvement in the conventionalwedge wire screen nozzle with few alterations (NOZZLE-A). The sameNOZZLE-A is shown with 3 d perspectives in the FIGS. No: 02D & 02E.These alterations create immaculate fluid collection/distributionprofile from its peripheral openings, which is required in accuratecollection/distribution of fluids in the processes.

FIGS. No: 02A & 02E shows modified wedge wire screen 02. Wedge wireprofiles 206 wound cylindrically, with pitch 208 a to form a screen 210a & welded with vertical rods 207 to form an open cylinder from itseither side. Threaded couplings 22B, 229 having external diameter nearlyequal to the cylinder of the screen 210 a is welded from either of itsopenings. At one end the coupling 229 height is kept minimum, just tointroduce a flow restrictor 30. The other end coupling 228 is standardto receive piping connection 34. Flow restrictor 30 is made of plastic(e.g. PP, PVDF, UHMWPE) having basic cylindrical shape, having threadedend 229 a matching for the short coupling end 229 for introducing insidethe screen cylinder 210 a. The fluid restrictor 30, has given tapernearly up to half-way mark of the screen 210 a height then it is turnedinto cylindrical shape 232 & finally conical tip 233. Cylindrical shape232 of the flow restrictor 30 passing through end coupling 228 makeswasher shape orifice 235 with internal face of the pipe connection 34.By manipulating the diameter of the cylindrical shape 232 of therestrictor 30, at the crossing with pipe connection 34, the flow can becontrolled.

The development of the equivalent of wedge wire in thermoplasticsinvolves in creating a circular ring which can be stacked on a conduitto receive/deliver fluid & for which the said ring must have followingfeatures:

-   -   (1) Nearly triangular shape at its cross section    -   (2) Thin (minimum thickness)    -   (3) Optimum width to offer minimum resistance to flow    -   (4) Supporting features on stacking    -   (5) Maximum fluid transporting angle (nearly 360°)

FIGS. No: 03A, 03B & 03C shows the features of stack ring of Type-1. Thestack rings are moulded from thermoplastics such as ‘PVDF, HDPE,Polypropylene’ etc. depending on the physical properties & chemicalresistance required These slack rings are stack-mounted on a conduithaving apertures for fluid transport to form different types of nozzlesor long lateral connecting to header pipe directly.

Stack ring of Type-1 is having width ‘w’ and thickness ‘t−0.25 mm’ wherethe aperture opening between two successive rings is 0.25 mm intended.The top side of the ring surface is having taper 13 a, while theopposite surface (bottom) is flat 13 b. To create peripheral apertureopenings in successive rings, after stacking & to support themcentrally, the rings are provided with lugs 14 of flat shape havingthickness ‘t’. The lugs 14 are the part of the ring (single mould)having tapered shape towards periphery & protruding towards the centreof the stack ring just like spoke of a wheel & touching the centralconduit 16 assigned for fluid transport. The surface of the lugs 14,just touching the central conduit 16 nearly follows the curvature 19 ofthe conduit. The flat bottom surface of the stack ring aligns with theflat surface of the lugs 14 (SECTION-III). The top tapered ring surfacecreates offset of thin gap (0.25 mm) where the lugs intersects the ring.When the rings are stacked centrally on a conduit 16, by keeping lugsaligned, they create uniform aperture 17, between two successive ringsas shown in the FIG. 03C & a vertical isolated port 15 between twoadjacent lugs. A thin fluid path 17 a is shown in the FIG. 03A.

To retain stack ring alignment on mounting central conduit, at least onelug is provided with rectangular extension 14 a to form a ‘male’interlock with the vertical slot of the conduit.

FIGS. No: 04A, 04B & 04C shows the features of stack ring of Type-2. Thestack rings are moulded from thermoplastics such as ‘PVDF, HDPE,Polypropylene’ etc. These stack rings have similar features just likestack ring of Type-1 with minor differences.

The top side & the bottom side of the ring surfaces 113 a are identical& having taper on both sides as shown in SECTION-IV. The lugs 114 arethe parts of the ring similar to the stack rings of Type-1, but arehaving offset of thin elevation on either of its side with respect tothe ring (Refer FIG. 04B) For example if a 0.25 mm aperture size isintended, then the lugs 114 have 0.125 mm offset on elevation on eitherside. FIG. No: 04C represents the aperture 117 created by to successiverings.

Referring to the crews sections (SECTION-III & IV) of both types of thestack rings, the taper angle given may variable. In our case we havemaintained it in between 6 to 8 degrees with respect to flat surface ofthe lugs 14, 114. To increase the effective life of the stack rings fromwear or erosion, the ring taper can be given by leaving a thin surfacestraight, at the peripheral entry of the ring (e.g. 0.25 mm). The tapergiven to these rings is actually identical to the wedge wire screenprofiles available.

Both the above given stack ring features are intended for nozzle designsfor ‘outside-in-flow’ applications, in which the media remains outsidethe screens. When the nozzle design is intended for ‘inside-out-flow’then the taper given to the stack rings follows exactly reversedirection with respect to the central longitudinal axis of the stacks,while the ring lugs 14 & 114 remain identical for the respective typesof the rings. In another method, the ring faces (13 a, 113 a—top & 13 b,113 b—bottom) can be kept flat (no taper) & the lugs having desiredelevation to create thin aperture.

FIG. No: 05A shows a sample nozzles (04) (NOZZLE-B) with the stackmounting. FIG. No: 06B shows vertical sections of the nozzles in whichwithout stack rings, for simplicity. Whereas FIG. No: 05C shows verticalcross section of the NOZZLE-B with flow restrictor (30 c) applied. Thetaper of the flow restricted (30 c) guides the incoming fluid from thenozzle (or a long lateral) outer stack-rings & apertures (120) on thecentral conduit of the nozzle.

All these nozzles are either machined from the rods of the plastics,such as ‘UHMWPE, PVDF, Polypropylene, HDPE etc. Ultra-High MolecularWeight Polyethylene (UHMWPE) is our first choice, as it is having lowestwear rate & easy machinability. However, moulding options of otherthermoplastics are also satisfactory with respect to costing, easiness &overall results.

Now referring to the FIGS. No: 05A & 05B, NOZZLE-B, 04 a; the nozzleconduit 122 holds the stack assembly 125 in between two open threadedends 111 & 111 a using check nuts or threaded rings 124, 124 a forlocking, respectively. Apertures 120 are assigned on the conduit percompiled channels for fluid transport. The flow restrictor (30 c) havingconical shape can be introduced at the end such that the taper ends atthe fluid inlet/outlet end. This flow restrictor achieves unique flowdistribution & collection. This type of nozzles can be connected inseries to form a distributor or collector lateral by using pipeconnection accessories. In this case, the fluid restrictor (30 c) isintroduced from the last (end) nozzle-section & its tapered end reachesthe inlet nozzle-section. Or the nozzle length can be extended toconvert it into a long collection/distribution lateral. Due to thelength extension, the fluid restrictor (30 c) can be given support atthe end, mechanically, instead of cantilever.

The sectional view (SECTION-V) of the NOZZLE-B, is shown in the FIG. No:06A. Stack ring 313, having tugs 314 nearly touching central conduit 322of the nozzle. The nozzle conduit 322 is having vertical rectangularslot 314 c, shown in the enlarged view, which receives extended lugs 314a of the stack rings for interlock. Apertures 320, in between adjacentlugs on the conduit 322, receives fluid in the direction 321 from thering periphery. A thin layer of fluid path 10 b is shown, which reflectsability of the stack ring to receive fluid from its periphery just likewedge wire screens.

FIG. No: 06B shows the blank stack ring 27, used to partition or toblock fluid channels of the stack ring nozzles already elaborated. Inthe front view, the SECTION-V) shows the stack thickness, which is justlike any washer.

FIG. No: 07A shows horizontal cross section of a cylindrical processingvessel & its “Header-Lateral” type distribution/collection system.Header (531) connecting transition header (531 a). The transition header(531 a) passing through the vessel body & connecting the inlet/outlet(535) piping. Header (531) having branch outlets for lateral connections(532) on its either side at equidistance. Flow restrictor (30) isintroduced in the header (531) which closes its dead end & having tapertowards the distribution/collection end. The laterals (532) areconstructed by connecting improved nozzles/strainers (539, 540, 541etc.) with the help of connecting piece (538). The connecting piece(538) can also be used for fixing laterals as support. The nozzles (539,540, 541 etc.) are having successively lower conduit diameter, asstarting from branch connection towards vessel wall to achieve equalhydraulics. These modifications applied are in such a way that, thenozzles distribution & collection achieve equalization effect, if themain header (531) has square/rectangular shape at its cross-section,then the flow restrictor will have square/rectangular shape withappropriate taper. In any type of header type distribution/collectionsystem the application of flow restrictor (30) maintains the appliedpressure of distribution evenly & its gives uniform collection via allbranching or collection apertures.

FIG. No: 07B shows a FRONT VIEW, SIDE VIEW & TOP VIEW of flow restrictor(30A). The round bar having diameter equal to the pipe—internal diameter(it may be header or lateral) has given two sided chamfer (534). The Rowrestrictor (30A) closes the dead-end of the pipe & its taper followstowards the distribution/collection end of the pipe from inside.

FIG. No: 07C shows flow restrictor (30A) applied in the header (531 c)having branching on its either sides (537). The taper (534) of the flowrestrictor (30A) end or nearly merges before inlet/outlet end (535) ofthe header.

FIG. No: 07D shows a FRONT VIEW, SIDE VIEW & TOP VIEW of flow restrictor(30B). The round bar having diameter equal to the pipe—internal diameter(it may be header or lateral) has given one sided chamfer (534). Theflow restrictor (308) closes the dead-end of the pipe & its taperfollows towards the distribution/collection end of the pipe from inside.

FIG. No: 07E shows the application of the flow restrictor (30B) in apipe, which could be a header or lateral (531E) having its branching(537B) at the one side (bottom). The flow restrictor (30B) closes thedead-end of the pipe & its taper follows towards the inlet/outlet end(535) of the pipe from inside.

The flow restrictor (30) can have simple conical shape taper, regardlessof the pipes branching, instead of the various shapes shown in the FIGS.No. 07B & 07C.

The preferred embodiments, in the different types of systems consideredhere, are subjected to minor changes or additions or standardizations &the same shall be covered by the given claims below.

1. An improvement in the conventional nozzles/screen for fluid flowdistribution/collection used in fluid flow processing units compriseswedge wire screen (02) of wedge wire profiles (206) wound cylindrically,with pitch (206 a) to form a screen (210 a) & welded with vertical rods(207) to form an open cylinder from its either side; and characterisedin that a pair of threaded couplings (228, 229) having external diameternearly equal to the cylinder of the screen (210 a) are welded fromeither of its openings; one of the said coupling (229) height is keptminimum, just to introduce a flow restrictor (30) and the said other endcoupling (228) is standard to receive piping connection (34); and thesaid flow restrictor (30) having basic cylindrical shape, havingthreaded end (229 a) matching with the said short coupling end (229) forintroducing inside the screen cylinder (210 a); the said fluidrestrictor (30), has given conical taper (231) nearly up to half-waymark of the screen (210 a) height, and thereafter turned intocylindrical shape (232) with conical tip (233), such that the saidcylindrical shape (232) of the flow restrictor (30) passing through endcoupling (228) makes washer shape orifice (235) with internal face ofthe pipe connection (34) for fluid flow control.
 2. The improvement inthe conventional screen/nozzle as claimed in claim 1 wherein the screen(210 a) cylindrical length of the screen may be extended to form adistribution/collection lateral-screen & therein the applied flowrestrictors' (30) length can be increased proportionately, such that itcloses the dead-end of the lateral mechanically from inside & theconical taper nearly ends at the distribution/collection (inlet/outlet)end of the said lateral-screen; and the said flow restrictor (30)cantilevered in the said screen-lateral by dead-end support.
 3. Animproved nozzles/screen for fluid flow distribution/collection used influid processing units comprises a cylindrical outer casing (125) ofscreen made of number of tapered, flat & circular stacked rings, each ofthem having tapered surface (13 a) towards centre on one side and flatother side (13 b) or tapered both sides (113 a, 113 c), having definedwidth and thickness with radially extending number of lugs (14, 114)formed therein with thickness slightly more than that of said ring togive desired openings between successive stack rings; and the said lugsresting on the periphery of a central conduit (122) having threaded endslocated at the centre of the said outer casing; and at least one lug (14a, 114 a) having extended length to engage into the vertical slot of thesaid conduit (314 c); the said conduit (122) provided with number ofholes (120) at distant in straight-line in each of channel formed byadjacent lugs (14, 114); the said outer casing held by check nut orthreaded ring (124,124 a) in the said conduit; and the entire saidassembled nozzle/screen having threaded ends (111, 111 a) for externalconnections.
 4. The nozzle/screen as claimed in claim 3 wherein; thesaid stack rings comprising at least one face (top or bottom/or both)tapered towards its centre; having horizontally flat supporting lugsradially immerging from the outer circumference of the ring towardsspoke directions at equal arc lengths; and the said lugs having extrathickness (vertically) making offset on the tapered side (or sides) ofthe ring to an extent the thin aperture is desired; and the extendedface of the said lugs have concave shape, thoroughly touching to thesaid central conduits' convex curvature surface; and the said lugs haveconical shape such that the sides tapering towards the outermostcircumference of the ring nearly emerging into a single point; and thesefeatured stack rings, when mounted on the nozzle, the adjacent lugs forma vertical partition creating isolated fluid channels in betweenadjacent lugs; and the said successive rings making a thin, uniform,circular gap at its circumference horizontally due to the offsetthickness of the flat lugs
 5. The nozzle/screen of claim 3, wherein thesaid central conduits (122) provided with at least one male-female typeinterlock (314 c) with the lugs of the said stack rings assembly; andthe said central conduit is applied with conical shape flow restrictor(30 c) enclosing it from one end whereas the tapered end reaching theinlet/outlet end of the said nozzle.
 6. The nozzle/screen of claim 3wherein the said cylindrical outer casing (125) formed can be extendedto form a distribution/collection lateral by increasing: a) the saidconduits' (122) length, b) the proportionate number of stack-rings, c)the said flow restrictors' (30 c) proportionate length & its conicaltaper, d) or connecting number of nozzles in series using suitablecouplings to form a lateral of desired length; & introducing singleflow-restrictor (30 c) in the said composite-lateral and saidlateral-screen formed connecting to main distribution/collection header.7. Flow restrictor (30A, 30B & 30 c) of claim 1, can be introduced ineach distribution/collection lateral-pipes & subsequent header-pipes,independently, with suitable size modification so as to equalize flow &pressure conditions in the individual distribution/collection laterals &screens, regardless of the type of nozzles/screens; and the said appliedmodification in the flow restrictor can be in its size & mode of endconnection within the pipe such as a. Introducing flow restrictor 30from opposite end of the header-lateral pipes with respect to theirfluid distribution/collection end & closing it mechanically e.g. withthreaded connections or flange type of end connections; b. The basicround bar-shaped flow restrictors' 30 taper, of chamfer shape, can bemanipulated either from ONE side towards distribution/collection end incase of a header having its lateral distribution points on ONE sideonly; and in another case the said flow restrictors' 30 taper of chamfershape can be manipulated from TWO sides towards distribution/collectionend in case of a header having its lateral distribution points on itseither side (two sides); and alternatively the flow restrictors' 30taper shape can be given in conical shape uniformly for any type oflaterals branching on header-pipe; c. The varied length of the appliedflow restrictor 30 in a pipe (either Header Or Lateral) has to be suchthat, the tapered end allows full bore water at the first inlet/outletbranch opening with respect to (w.r.t.) distribution/collection nozzleend.
 8. Flow restrictor of claim 7, when applied in the headers of thedistribution/collection system, having near square or rectangular shapeat its' cross-section, then the said flow restrictor, thereincharacterised with square or rectangular shape at its' cross-section, soas to match the said header & the taper applied to the said flowrestrictor.